Very friendly alien in copse (7)
I believe the answer is:
thicket
'copse' is the definition.
(I know that copse can be written as thicket)
'very friendly alien' is the wordplay.
'very friendly' becomes 'thick' (I've seen this before. I am not sure about the 'very' bit.).
'alien' becomes 'et' (extraterrestrial).
'thick'+'et'='THICKET'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for thicket that I've seen before include "Dense group of trees or bushes" , "Dense growth of bushes" , "Coppice" , "Mass of shrubs and bushes growing close together" , "Mass of shrubs and small trees growing close together" .)